*1.1. Motivation and Literature Review*

Due to the rapid development of the economy and the advancement of urbanization, the highly intensified exploitation of spatial resources has become a distinctive feature of urban and rural spatial development processes. As the number of spatial resources is limited, while their functions are highly adjustable, different groups utilize these resources in various intensities to meet their own interests, and therefore, the use of spatial resources is at times not in line with the ecological environment protection. As a result, a series of

**Citation:** Xi, F.; Wang, R.; Shi, J.; Zhang, J.; Yu, Y.; Wang, N.; Wang, Z. Spatio-Temporal Pattern and Conflict Identification of Production–Living– Ecological Space in the Yellow River Basin. *Land* **2022**, *11*, 744. https:// doi.org/10.3390/land11050744

Academic Editor: Dong Jiang

Received: 15 April 2022 Accepted: 15 May 2022 Published: 18 May 2022

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spatial conflicts have emerged, such as the uncontrolled expansion of urban space, the imbalance between agricultural space and ecological space, the degradation of ecosystems due to the encroachment of ecological space, and the unreasonable layout and function of various spaces within cities.

The human–land space competition and conflict of interests caused by land use have gradually become a hot issue in the international community [1], receiving close attention from global stakeholders such as NGOs, the United Nations, and governments [2,3]. To properly alleviate land-use conflicts, the Food and Agriculture Organization of the United Nations (FAO) formulated and promulgated the Land Evaluation Outline, proposing that land-use planning should be carried out scientifically based on land suitability. Accordingly, countries around the world established their own land-use suitability evaluation systems on the basis of this outline, for the purposes of coordinating the relationship between land resource supply and human demand and realizing the sustainable use of land resources [4]. At the same time, studies on land-use conflicts, concerning the areas of society, economy, geography, and environment are increasing in academia [5–9]. Research in this area is mainly focused on the sources, types, identification, evolution, and management of spatial conflicts [10–18].

Spatial resources can be functionally divided into three types: production space, living space, and ecological space [19]. Production–living–ecological space (PLES) basically covers the scope of spatial activities of human work and life and is the basic carrier of human socio-economic development. As the main body of the optimization of the spatial pattern of territorial space, PLES becomes an important basis for the implementation of the main functional area planning at all levels, the construction of the spatial planning system, and the improvement of the spatial development and protection system of the territorial space [20].

Spatial conflict in PLES is mainly manifested by the imbalance of structure and function of PLES, inappropriate territorial combination, and uncontrolled transformation of spatial types. In particular, it reveals the unreasonable occupation of living and ecological spaces by production space and the destruction of ecological space by spaces of living and production. The identification of spatial conflict of PLES, simulation of spatial conflict pattern in PLES, and analysis of its development and evolutionary characteristics can effectively reveal the complexity and vulnerability of the human–land relationship, fully reflecting the results and characteristics of spatial resource competition in the process of human–land interaction, and provide basic support for the optimization of regional territorial development and protection pattern [21].

The spatial conflict of PLES, in essence, belongs to the category of land-use conflicts. The study of land-use conflicts dates back to the 18th century and was initially focused on the conflict between the added economic value of land, human demand, and the land system [22]. Since the 1960s and 1970s, land-use conflicts have been characterized by interdisciplinary and diversified integration, and scholars' research perspectives have been enriched, revealing the causes, forms, and characteristics of land-use conflicts in relation to different dimensions such as regional deprivation [23–25], spatial competition [26–28], spatial integration [29–31], spatial control [32–36], ecological security [37], non-cooperative games [38], energy security and climate change [39], etc., as well as their impacts on socioeconomic development and resources. In terms of research content, the spatial spillover effects of talent, policy, capital, technology, and resources [40–42] have been explored, the conflicts in spatial resource utilization between different interest groups and conflicts between spatial utilization and regional ecological environmental protection [43,44] have been analyzed, the conflicts in land-use subjects, land planning, and land systems [45–47] have been evaluated, and the spatial conflicts have been measured from the perspectives of economics and ecology, respectively. This body of research provides a basic framework for exploring the process of urbanization to promote the stability and harmony of human–land relationships and optimize the regional ecological security pattern. In terms of evaluation methods, scholars have mainly adopted the participatory survey method [48], PSR model and fuzzy evaluation method [49], multiobjective planning method [50], land– scape pattern analysis method [21,37], coupled coordination degree method [51], suitability evaluation [52,53], and actor–network analysis method [54], focusing on the scale of administrative regions such as urban agglomerations, provinces, and cities or special regions such as mining areas [45,55], and initially built a theoretical framework and methodological system for spatial conflict research.

To ensure that production space is used intensively and efficiently, living space is pleasant and proper in size, and ecological space is unspoiled and beautiful are important goals to realize the construction of ecological civilization in China [56]. From 2012 to 2017, the central working conference of urbanization, the 13th Five-Year Plan, and the report of the 19th National Congress of China set the coordinated development of the PLES as an essential strategic initiative to enhance the modernization of the spatial governance system and governance capacity of the country. How to alleviate the spatial conflicts among different PLES systems has become a primary issue that needs to be solved [57].

Although scholars have made some progress in spatial conflict identification, there are still certain shortcomings. First of all, at the spatial scale, previous studies mainly focus on administrative units such as urban agglomerations, provinces, and cities, and there are fewer studies at the watershed scale; in terms of research content, previous studies on spatial conflicts mostly concerned the space of land-use types, and there are fewer studies on the analysis of conflicts within the PLES system; at the temporal scale, most of the research considered the current situation of spatial conflicts, but less attention has been given to the evolution of future spatial conflicts. This becomes particularly important in the context of the recent emphasis on nature-based solutions for climate change mitigation [58].
